Geoengineering: Challenges and global impacts

The Institute of Physics, the Royal Society of Chemistry and the Royal Academy of Engineering held a joint seminar at the House of Commons on 15 July 2009 to explore approaches to managing climate change based on strategic engineering of the environment on a global scale.

This seminar is the latest in a series demonstrating key routes by which contemporary physics, chemistry and engineeringaffect life in the 21st century.

Geoengineering provides a set of options in which the Earth’s climate is deliberately manipulated to offset the effectsts of global warming due to increasing levels of greenhouse gases in the atmosphere. The various proposals offer the potential to mitigate the worst effects of climate change, in some scenarios quite quickly, so buying more time to make the necessary reductions in man-made carbon dioxide (CO2) emissions.

The seminar focused on several imaginative proposals and also considered the social and political implications of attempting to implement such technologies. Dr Brian Iddon MP, vice-president of the Parliamentary and Scientific Committee and member of the House of Commons Innovation, Universities, Science and Skills Committee (now the Science and Technology Committee), chaired the meeting. Dr Alan Gadian of the University of Leeds proposed a cloud-whitening strategy to reflect more solar radiation back into space and thus cool the planet. Dr Dan Lunt of the University of Bristol described a space-based scheme using mirrors to reflect sunlight away from the Earth. Prof. Andrew Watson of the University of East Anglia summarised methods of fixing atmospheric carbon by stimulating the growth of marine algae. Finally, Prof. Steve Rayner from the University of Oxford discussed public acceptability and policy issues relating to geoengineering schemes.